Production lines for tobacco products often involve processing long rod shaped articles in a series fashion either continuously or through a series of drums to obtain a desired final result. Such a production line can comprise a plain cigarette processing apparatus (a cigarette rod maker or “maker”), such as by way of example a machine that is available from Hauni Machinenbau AG of Hamburg, Germany under the trade name PROTOS, a filter rod apparatus (“tipping machine”), such as by way of example a machine that is available from Hauni Machinenbau AG of Hamburg, Germany under the trade name MAX, and a packing machine.
There are a number of patents related to the delivery of particles to filter assemblies that are manufactured in a serial stream. For example, U.S. Pat. No. 4,411,640 to Hall discloses an apparatus for forming filter mouthpieces wherein plugs are fed in a serial manner. Gaps are formed using a separating means and these gaps are filled with material by a media wheel. U.S. Pat. No. 5,221,247 to Budjinski, II et al. teaches a similar device and method.
There are also patents related to the assembly techniques of filter combining. For instance, U.S. Pat. No. 3,306,306 to Rudszinat teaches a well known two hopper design for the production of filter components. Standard sized filter rods are fed from two hoppers to a series of cutting, staggering, spreading and alignment drums. Depending on which hopper and corresponding drums the filter passes though, filters of a first or second size will be produced. U.S. Pat. No. 4,815,481 to Hirose et al. also teaches two hopper design for feeding filter tips and tip halves through machinery to join these two components together with cigarettes.
U.S. Pat. No. 3,308,832 to Stelzer et al. discloses a method of production for forming filter mouthpieces of ultimate or unit length comprising two rod shaped outer filters of identical material and intermediate or inner filters of granular material. Also disclosed is a method and apparatus for forming multiple intermediate filters of a unit size to form a more complex filter.
U.S. Patent Application Publication 2003/0034085 teaches an apparatus and method for filling cavities with metered amounts of granulated particles.
In contrast, the present invention provides parallel combining of filter components, the filling of cavities in a parallel method, and the addition of a paper cap.
One of the limitations of the prior technologies used to combine filter components is the registration (positions) of the components to each other as well as to the final cut of the filter assembly. The process of transferring multiple components into the serial stream often results in unintentional gaps, components having the wrong lengths, or the total lack of a component being present. In addition to these issues, once the serial filter assembly is wrapped and sealed in a paper, the continuous serial filter assembly is then cut into lengths. This cutting process creates two additional areas where non-conforming products are produced: Cut registration and overall filter length. In contrast, the present invention provides techniques which eliminate most if not all of these issues. While the issue of unintentional gaps between components is not completely eliminated in these techniques, the impact on the finished product will be minimized. In prior processes, unintentional gaps between filter components cause the entire serial stream to change position and could affect the final cut registration. In contrast, the process provided by the present invention ensures that the inconsistent assembly of components will only affect the one filter assembly. Inspection techniques will allow the non-conforming assemblies to be identified and removed.
Furthermore, according to prior techniques for the filling of cavities, the possibility of these particles ending up trapped outside the pocket region but under the filter wrap exceeds acceptable limits. These particles would be rendered visible to the consumer by, for instance, ending up in an area near the exposed end of the filter when it is combined with the cigarette and wrapped with tipping paper. The prior art used several different methods to eliminate this possibility. Techniques to inspect filters for this scatter or combining the filter assembly with an additional solid acetate filter component to cap the end of the product, are examples of two methods used in the prior art. Both of these methods are expensive, increase production waste, and complicate the entire manufacturing process.
The techniques provided by the present invention achieve almost complete elimination of particle scatter. Because the first paper wrap is attached to the filter component assembly prior to the cavity filling process, the possibility for the particles to be trapped between the paper and the filter components is minimized. While it is not guaranteed that all of the particles transferred from the drum end up in the cavity, there is no area where the particle can come to rest on the surface of the filter assembly. Once the paper cap is applied, the particles are retained in the cavities.
Prior methods for the assembly of combined filters are also limited by several factors relating to productivity. In the process of combining two different components to make a plug filter assembly, the techniques used to transfer the assembly into a serial stream so paper can be applied and the filter assembly cut is normally limited to less than 400 meters per minute. As the make up of the components increase in complexity or the addition of cavities filled with particles are introduced, this maximum speed drops to less than 250 meters per minute. Using a typical 108 millimeter filter as an example, these prior processes can produce 1,900 to 3,800 filter assemblies per minute, the limiting factor being the ability to deliver particles from the delivery drum to the cavities. Past experience indicates that these prior processes can operate effectively and efficiently up to linear speeds of 300 meters per minute. In contrast, the present invention provides a parallel method that can produce up to 8,000 filters per minute.
Finally, the present invention provides a process which significantly reduces material waste, particularly at machine startup and machine stoppage. Waste reductions from minimizing non-conforming filters should also be realized.